False, says the Centers for Disease Control and Prevention (CDC). The flu vaccine contains killed viruses, which means the flu shot cannot cause infection. Some people notice flu-like symptoms immediately after getting a shot, but that can be from your immune system making antibodies to the killed viruses in the vaccine.

2. The nasal flu vaccine can give you the flu.

False (for most people). Unlike the flu shot, which contains killed viruses, the nasal spray vaccine does contain live viruses. However, the viruses contained in the nasal-spray vaccine are weakened, which means they cannot cause flu illness in most people. These weakened viruses are designed to cause mild infection at the cooler temperatures found within the nose, but they cannot infect the lungs or other warmer areas of the body. However, it should only be given to people "who do not have an underlying medical condition that predisposes them to influenza complications," according to the CDC.

3. The flu shot doesn’t work half of the time.

False. The flu shot actually works more than half of the time. According to the CDC, the flu shot appeared to be about 60 percent effective for all age groups combined in the 2010-11 season. In earlier years, the effectiveness rates have been as high as 90 percent.

4. Getting the flu is no big deal.

False. The flu can cause illness and even death. Over the past 30 years, the flu has been linked to more than 200,000 hospitalizations a year. It’s a serious disease, particularly among young children, older adults and people with certain chronic health conditions such as asthma, heart disease and diabetes.

5. You should get the flu shot in the winter.

False. You should get the flu shot earlier in the year; most clinics start offering the flu shot in October.

6. You don’t need a flu shot this year if you had one last year.

False. The CDC recommends a yearly flu vaccine for people 6 months and older. □